In an interview with Variety, Matthew McConaughey said, regarding Cohle, I wanted to get in that dudes head. The obsession, the island of a man - Im always looking for a guy who monologues. Its something really important as I feel Im going into my better work. Going slightly more method than usual, McConaughey mostly kept himself to himself on set, even keeping his distance from pal Harrelson. It took some soul-searching to get McConaughey where he wanted to go, culminating in some lengthy in-depth writing: I just basically broke it down and made a 450-page graph of where Cohle was and where he was coming from.